System.Log.Heavy.Backends

Documentation

This module contains several implementation of logging backend. A backend is some kind of target, where your messages will go. Each backend has its own specific settings.

Backends provided are:

• Fast-logger backend. It allows to write messages to stdout, stderr or arbitrary file.
• Syslog backend.
• Chan backend.

data FastLoggerSettings

Settings of fast-logger backend. This mostly reflects settings of fast-logger itself.

Constructors

FastLoggerSettings

Fields

• lsFilter :: LogFilter

  Log messages filter

• lsFormat :: Format

  Log message format

• lsType :: LogType

  Fast-logger target settings

Instances

IsLogBackend FastLoggerSettings

Methods

withLoggingB :: MonadIO m => FastLoggerSettings -> (m a -> IO a) -> LoggingT m a -> m a

data SyslogSettings

Settings for syslog backend. This mostly reflects syslog API.

Constructors

SyslogSettings

Fields

• ssFilter :: LogFilter

  Log messages filter

• ssFormat :: Format

  Log message format. Usually you do not want to put time here, because syslog writes time to log by itself by default.

• ssIdent :: String

  Syslog source identifier. Usually the name of your program.

• ssOptions :: [Option]

  Syslog options

• ssFacility :: Facility

  Syslog facility. It is usally User, if you are writing user-space program.

Instances

IsLogBackend SyslogSettings

Methods

withLoggingB :: MonadIO m => SyslogSettings -> (m a -> IO a) -> LoggingT m a -> m a

Default settings

defStdoutSettings :: FastLoggerSettings

Default settings for fast-logger stdout output

defStderrSettings :: FastLoggerSettings

Default settings for fast-logger stderr output

defFileSettings :: FilePath -> FastLoggerSettings

Default settings for fast-logger file output. This implies log rotation when log file size reaches 10Mb.

defaultSyslogSettings :: SyslogSettings

Default settings for syslog backend

defaultSyslogFormat :: Format

Default log message format fof syslog backend: [{level}] {source}: {message}

Utilities for other backends implementation

checkLogLevel :: LogFilter -> LogMessage -> Bool

Check if message level matches given filter.